#region Copyright & License

//
// Copyright 2001-2005 The Apache Software Foundation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

#endregion

using System;

namespace log4net.Core {
  /// <summary>
  /// A SecurityContext used by log4net when interacting with protected resources
  /// </summary>
  /// <remarks>
  /// <para>
  /// A SecurityContext used by log4net when interacting with protected resources
  /// for example with operating system services. This can be used to impersonate
  /// a principal that has been granted privileges on the system resources.
  /// </para>
  /// </remarks>
  /// <author>Nicko Cadell</author>
  public abstract class SecurityContext {
    /// <summary>
    /// Impersonate this SecurityContext
    /// </summary>
    /// <param name="state">State supplied by the caller</param>
    /// <returns>An <see cref="IDisposable"/> instance that will
    /// revoke the impersonation of this SecurityContext, or <c>null</c></returns>
    /// <remarks>
    /// <para>
    /// Impersonate this security context. Further calls on the current
    /// thread should now be made in the security context provided
    /// by this object. When the <see cref="IDisposable"/> result 
    /// <see cref="IDisposable.Dispose"/> method is called the security
    /// context of the thread should be reverted to the state it was in
    /// before <see cref="Impersonate"/> was called.
    /// </para>
    /// </remarks>
    public abstract IDisposable Impersonate(object state);
  }
}